The invention relates to novel resin compositions having improved adhesion to polyurethane foam. The invention also relates to a method for improving adhesion between a resin composition and polyurethane foam.
Thermoplastic resins have become of interest in recent years as a replacement for metal in the interior parts of automobiles, such as the manufacture of instrument panels, top covers and arm rests in the interior of the car. In these applications one requirement of the thermoplastic resin is that it must adhere to the polyurethane foam that is often used as a covering. Resin compositions containing polyphenylene ether and polyolefins, e.g., polypropylene, as their primary constituents are generally known and are especially attractive for these automotive applications because of their excellent chemical resistance, high impact strength, low relative cost, and good dimensional stability.
U.S. Pat. No. 4,713,416 to Del Giudice et al. generally describes compositions comprising (a) a polyphenylene ether, (b) a thermoplastic polymer incompatible with the polyphenylene ether, and (c) a polymeric compatibility-promoting agent comprising one or more blocks of vinylaromatic monomer units compatible with the polyphenylene ether (a) and one or more blocks of monomeric units of the same nature as the thermoplastic polymer (b) or compatible with that polymer.
U.S. Pat. No. 4,764,559 to Yamauchi et al. generally describes a composition comprising (a) a polyphenylene ether having a low degree of polymerization, with or without a styrene resin, (b) a polyolefin, and (c) a styrene compound/conjugated diene block copolymer or a hydrogenation product thereof.
U.S. Pat. No. 4,863,997 to Shibuya et al. generally describes a composition comprising (a) a polyolefin resin, (b) a polyphenylene ether resin, and (c) a hydrogenated block copolymer of an alkenyl aromatic compound and a conjugated diene which contains 45–80 weight percent of a repeating unit derived from the alkenyl aromatic compound.
U.S. Pat. No. 4,994,508 to Shiraki et al. generally describes a composition comprising (a) 1–99 parts by weight of a specific hydrogenated block copolymer having at least one polymer block composed mainly of a vinyl aromatic compound and at least one polymer block composed mainly of a conjugated diene compound, and (b) 99–1 parts by weight of at least one thermoplastic substance selected from the group consisting of tackifier resins, thermoplastic resins, and bituminous materials. Thermoplastic resins include polyethylenes, polypropylenes, and polyphenylene ethers, among many others.
U.S. Pat. No. 5,071,912 to Furuta et al. generally describes a composition comprising (a) a polyphenylene ether, (b) a styrene-modified propylene polymer or a composition containing a styrene-modified propylene polymer and polypropylene, and (c) at least two rubbery substances, one being compatible with (a) and the other incompatible with (a).
U.S. Pat. No. 5,081,187 to Maruyama et al. generally describes a composition comprising specific amounts of (a) a polyolefin, (b) a polyphenylene ether, (c) a partially hydrogenated alkenyl aromatic compound-isoprene block copolymer, and (d) an alkenyl aromatic compound-conjugated diene block copolymer.
U.S. Pat. No. 5,418,287 to Tanaka et al. generally describes a composition comprising (a) a polyphenylene ether, (b) a crystalline polyolefin resin, and (c) a graft copolymer where the backbone is a copolymer of (i) ethylene or at least one C3–C 2 alpha-olefin, and (ii) at least one chain non-conjugated diene.
U.S. Pat. No. 6,031,049 to Chino et al. generally describes a composition comprising specie c amounts of (a) a component composed of syndiotactic polystyrene and a polyolefin, (b) a block or graft styrene-olefin copolymer having a styrene content of 40 to 85% by weight, and (c) a polyphenylene ether.
European Patent Application No. 412,787 A2 to Furuta et al. generally describes compositions comprising (a) a polyphenylene ether, (b) a propylene polymer modified by grafting with a styrene-based monomer alone or in combination with another copolymerizable monomer, with or without an unmodified propylene polymer, and (c) a rubbery substance having chain A miscible with all or part of (a) and chain B miscible with all or part of (b).
U.S. Pat. No. 6,495,630 to Adeyinka et al. generally describes thermoplastic compositions that include specified amounts of poly(arylene ether), a polyolefin, a rubber-modified poly(alkenyl aromatic) resin, a hydrogenated block copolymer, an unhydrogenated block copolymer, and an ethylene/alpha-olefin elastomeric copolymer
Chao et al. in U.S. Pat. No. 5,756,196 disclosed a composition and method for improving the adhesion of compositions of polyphenylene ether and polystyrene resins to polyurethane foam using primary-amine or secondary-amine containing material.
However, achieving desirable levels of adhesion to polyurethane foam to compositions containing substantial amounts of polyolefins is difficult due to low reactivity and/or surface energy of the polyolefin in these compositions. Thus, there remains a need for compositions of polyphenylene ether and polyolefins, especially polypropylene, that retains the properties of the compositions and that will also provide improved adhesion with polyurethane foam.